COGNITION AND WHITE-MATTER HYPERINTENSITIES IN OLDER DEPRESSED-PATIENTS

Objective: The authors compared amounts of white matter hyperintensity in late- and early-onset depressed patients and never-depressed older subjects, compared neuropsychological function in these groups, and i nvestigated the association between white matter hyperintensities and cognitive function in depression. Method: Sixty currently depressed pa tients whose first depression occurred after age 50 years, 35 depresse d patients over age 50 whose first depression occurred before age 35, and 165 nonpsychiatrically ill subjects over age 50 underwent magnetic resonance imaging (MRI) and neuropsychological evaluation. Areas of w hite matter hyperintensity were measured from MRI images. Results: The late-onset patients had more white matter hyperintensity than either of the other groups. Compared to the nondepressed subjects, the patien ts had significantly lower scores in the cognitive domains of nonverba l intelligence, nonverbal memory, constructional ability, executive ab ility, and information processing speed The cognitive abnormalities we re mostly confined to the late-onset patients, and the presence of a l arge amount of white matter hyperintensity runs associated with signif icantly poorer executive skills. However, most of the scores were not in the significantly impaired range. Conclusions: Large amounts of whi te matter hyperintensity are more frequent in patients with late-onset depression than in elderly subjects with early-onset or no depression . Both late- and early-onset elderly depressed patients show mild decr ements in some ''right hemisphere'' cognitive skills; the late-onset s ubjects also show deterioration in information processing speed and ex ecutive functions. Patients with large amounts of white matter hyperin tensity have significantly poorer executive function.